Method and system for plaque characterization

摘要

A method of quantifying plaques imaged by cardiac computed tomography angiography (“CCTA”) scan data. Calcified and non-calcified component thresholds are determined based at least in part on attenuation values of a pool of blood in the CCTA scan data. An epicardial fat threshold is determined and used to classify epicardial fat in the CCTA scan data. A portion of CCTA scan data positioned between a detected outer boundary of the coronary artery and a portion classified as lumen is classified as arterial wall. NCP and CP seeds are identified in the arterial wall portion. Portions of the CCTA scan data continuous with a NCP seed and having attenuation values greater than an artery wall value and less than the NCP threshold are classified as NCP, and portions of the CCTA scan data continuous with the CP seed and having attenuation values greater than the CP threshold are classified as CP.

主权项

1. A computer implemented method comprising:
obtaining cardiac computed tomography angiography (“CCTA”) scan data comprising a plurality of attenuation values, the CCTA scan data imaging a pool of blood, and a coronary artery having a lumen defined by an artery wall at least partially surrounded by epicardial fat; receiving an identification of a first portion of the plurality of attenuation values, the first portion being located within the pool of blood; receiving identifications of a plurality of points positioned within the lumen of the coronary artery; determining a calcified component threshold based at least in part on the first portion of the plurality of attenuation values; generating one or more centerlines from the plurality of points; determining a vessel neighborhood based on the one or more centerlines; generating a series of short-axis cross-sections through the coronary artery based on the one or more centerlines, each of the short-axis cross-sections comprising a point positioned on one of the one or more centerlines; within each of the series of short-axis cross-sections, identifying at least one epicardial fat region within the vessel neighborhood; determining an epicardial fat threshold (“EFT”) value based on ones of the plurality of attenuation values within the epicardial fat regions identified within each of the series of short-axis cross-sections; within each of the series of short-axis cross-sections, classifying portions of the short-axis cross-section having attenuation values below the EFT value as epicardial fat; determining a non-calcified component threshold based at least in part on the first portion of the plurality of attenuation values; classifying as lumen a connected portion of CCTA scan data adjacent the one or more centerlines and having attenuation values greater than the non-calcified component threshold and less than the calcified component threshold; within each of the series of short-axis cross-sections, detecting an outer boundary of the coronary artery in the short-axis cross-section, and classifying as arterial wall a portion of CCTA scan data positioned between the outer boundary of the coronary artery and the portion classified as lumen; determining an artery wall value as a function of the ones of the attenuation values located within the portion of the CCTA scan data classified as arterial wall; identifying at least one of a non-calcified component seed element and a calcified component seed element in the portion classified as arterial wall; for each non-calcified component seed element identified, classifying as non-calcified components any portions of the CCTA scan data continuous with the non-calcified component seed element and having attenuation values that are greater than the artery wall value and less than the non-calcified component threshold value; and for each calcified component seed element identified, classifying as calcified components any portions of the CCTA scan data continuous with the calcified component seed element and having attenuation values that are greater than the calcified component threshold value.